1. Field of the Invention
The present invention relates to the electric and hybrid vehicles, and more particularly, to a regenerative torque shifter that provides for manual control of the degree of regenerative braking by the driver of an electric or hybrid electric vehicle.
2. Description of the Related Art
Electric and hybrid electric vehicles are becoming more commonplace. Many of these vehicles include a system that automatically switches the electric motor into a generator as the vehicle is slowed, which provides regenerative braking. Such regenerative brake systems conserve energy so that batteries can be recharged from energy that would otherwise be dissipated as heat, thus increasing the range and energy efficiency of the vehicle. The amount of braking in such systems is either regulated automatically by the system, or statically by the operator.
A by-product of manual or semi-automatic transmissions found in internal combustion engine (ICE) driven vehicles is a process commonly referred to as “downshifting,” generally referring to deceleration that occurs when the driver's foot is removed from the accelerator and resulting from friction and air pressure in the cylinders, as well as decreased flow of air-fuel mixture into the combustion chamber. Downshifting is a well-known and critical component in the high-performance driving world. Downshifting is used to reduce vehicle speed when entering turns to increase traction. In addition, downshifting reduces the amount of time the operator needs to move their foot from the accelerator to the brake to slow the vehicle down, a significant improvement in safety. Electric vehicles do not naturally incur this phenomena, and hybrid vehicles only to a limited extent, depending upon the configuration of the vehicle. It would be desirable to provide this downshifting feature in electric vehicles and hybrid vehicles to provide such vehicles with the same feel as an ICE vehicle.
Thus, a regenerative torque shifter solving the aforementioned problems is desired.